Conventional optical module packages are known which include an optical waveguide device formed with a plurality of branched optical waveguides connected with an optical fiber and having the device accommodated in a housing.
A problem with conventional optical module packages is that an adhesive typically applied to a portion where the optical waveguides are connected with the optical fiber absorbs moisture and thereby decreases in adhesive strength between the optical waveguides and the optical fiber.
A conventional approach to address the problem is to fix a fiber unit to a housing an adhesive or resin during manufacture of an optical module package, such that a fiber unit including an optical waveguide device and an optical fiber connected to each other is accommodated in the housing. By way of example, the following references are identified: Japanese Laid-open Patent Publication No. H7-92342 (also referred to as Patent Document 1); Japanese Laid-open Patent Publication No. H8-94875 (also referred to as Patent Document 2); Japanese Laid-open Patent Publication No. 2006-30552 (also referred to as Patent Document 3); and Japanese Laid-open Patent Publication No. S63-205617 (also referred to as Patent Document 4). However, because the fiber unit is fixed to the housing an adhesive or resin in the case of the optical module package disclosed in each of above Patent Documents, the following problems have not been solved.
In general, adhesives are often expensive. Further, in the case of using an adhesive, great attention needs to be paid to prevent the adhesive from adhering to other parts during the process of manufacturing the optical module package, and a process of curing the adhesive after application of the adhesive to a member is required. In particular, at the time when the fiber unit is fixed to the housing the adhesive, the adhesive needs to be injected or the like into the housing. At the injection or the like, the adhesive sometimes adheres to unintended locations of the housing, and avoidance of the adhesion requires effort.
Also in the case of using resin, there is a problem in which a process of curing the resin is required after filling it in the housing, and therefore time and effort is required for manufacture. Accordingly, the optical module package in a structure in which the fiber unit is fixed to the housing an adhesive or resin has a problem of requiring time and effort for manufacture.
Alternatively, there is another approach of using a spacer other that the above in order to fix the fiber unit in the housing. However, since the spacer needs to be fixed to the housing an adhesive or resin also in this case, the problem of requiring effort and time for manufacture has not been able to be solved.
With further regard to the Patent Documents 1 to 4, the disclosed optical module packages disclosed have a structure in which the optical fiber is inserted into a tubular member or an insertion hole provided in the housing. Therefore, the optical module packages according to these references requires more effort and time for manufacture due to insertion work of the optical fiber which cannot be avoided in the process of manufacture.
In this regard, the work of inserting the optical fiber into the tubular member or the like can be made unnecessary in the optical module package disclosed in Japanese Laid-open Patent Publication No. H10-206681 (also referred to as Patent Document 5). However, in the case of this optical module package, a plurality of kinds of resins need to be filled in the housing after the fiber unit is accommodated in the housing. In addition, a process of curing each resin needs to be performed every time when each resin is filled, and therefore much time and effort are required for manufacturing processes.
As described above, it is difficult to reduce the effort and time required for manufacture in the respective conventional arts because the fiber unit is fixed to the housing an adhesive or resin.